Chemistry 12th Edition

At 25$^{\circ}$C, the $K_w$ is $10^{-14}$, therefore: $pH + pOH = 14$ $pOH = 14 - pH$ (a) $pOH > 7$ $14 - pH > 7$ $- pH > -7$ $pH < 7$ Therefore: $pH < pOH$ $-log[H^+] < -log[OH^-]$ $log[H^+] > log[OH^-]$ Which means: $[H^+] > [OH^-] : Acidic$ (b) pOH = 7 $14 - pH = 7$ $pH = 7$ Therefore: $pH = pOH$ : Neutral. (c) $pOH < 7$ $14 - pH < 7$ $- pH < -7$ $pH > 7$ Therefore: $pH > pOH$ $-log[H^+] > -log[OH^-]$ $log[H^+] < log[OH^-]$ Which means: $[H^+] < [OH^-] : Basic$